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[Federal Register Volume 81, Number 23 (Thursday, February 4, 2016)]
[Rules and Regulations]
[Pages 5893-5896]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-01827]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2015-1983; Directorate Identifier 2015-NM-020-AD; 
Amendment 39-18388; AD 2016-03-01]
RIN 2120-AA64

Airworthiness Directives; the Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for all The 
Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series 
airplanes. This AD was prompted by a report of a crack of the forward 
leg of the left front spar lower chord and cracks on the lower wing 
skin at three fastener holes common to the nacelle outboard side load 
fitting. This AD requires repetitive inspections for cracks on the 
front spar lower chord, inspar skin, and wing skin, and corrective 
action if necessary. We are issuing this AD to detect and correct 
fatigue cracking of the forward leg of the front spar lower chord, 
inspar skin, and wing skin common to the nacelle outboard side load 
fitting, which could adversely affect the structural integrity of the 
wing.

DATES: This AD is effective March 10, 2016.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of March 10, 
2016.

ADDRESSES: For service information identified in this final rule, 
contact Boeing Commercial Airplanes, Attention: Data & Services 
Management, P.O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; telephone 
206-544-5000, extension 1; fax 206-766-5680; Internet https://www.myboeingfleet.com. You may view this referenced service information 
at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., 
Renton, WA. For information on the availability of this material at the 
FAA, call 425-227-1221. It is also available on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2015-
1983.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2015-

[[Page 5894]]

1983; or in person at the Docket Management Facility between 9 a.m. and 
5 p.m., Monday through Friday, except Federal holidays. The AD docket 
contains this AD, the regulatory evaluation, any comments received, and 
other information. The address for the Docket Office (phone: 800-647-
5527) is Docket Management Facility, U.S. Department of Transportation, 
Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 
New Jersey Avenue SE., Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Jennifer Tsakoumakis, Aerospace 
Engineer, Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft 
Certification Office (ACO), 3960 Paramount Boulevard, Lakewood, CA 
90712-4137; phone: 562-627-5264; fax: 562-627-5210; email: 
jennifer.tsakoumakis@faa.gov.

SUPPLEMENTARY INFORMATION: 

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 by adding an AD that would apply to all The Boeing Company 
Model 737-100, -200, -200C, -300, -400, and -500 series airplanes. The 
NPRM published in the Federal Register on June 24, 2015 (80 FR 36258) 
(``the NPRM''). The NPRM was prompted by a report of a crack of the 
forward leg of the left front spar lower chord and cracks on the lower 
wing skin at three fastener holes common to the nacelle outboard side 
load fitting. The NPRM proposed to require repetitive inspections for 
cracks on the front spar lower chord, inspar skin, and wing skin, and 
corrective action if necessary. We are issuing this AD to correct the 
unsafe condition on these products.

Comments

    We gave the public the opportunity to participate in developing 
this AD. The following presents the comments received on the NPRM and 
the FAA's response to each comment.

Support for the NPRM

    Boeing stated that it concurs with the NPRM.

Effect of Winglets on Accomplishment of the NPRM

    Southwest Airlines (SWA) requested clarification whether the 
installation of Aviation Partners Boeing (APB) Supplemental Type 
Certificate (STC) ST01219SE (http://rgl.faa.gov/
Regulatory_and_Guidance_Library/rgstc.nsf/0/
ebd1cec7b301293e86257cb30045557a/$FILE/ST01219SE.pdf) has any affect to 
the ability of accomplishment of the action of this proposed AD (80 FR 
36258, June 24, 2015). APB stated that the installation of winglets per 
STC ST01219SE does not affect the accomplishment of the manufacturer's 
service instructions.
    We concur with APB's comment and agree to clarify. We have 
redesignated paragraph (c) of the proposed AD (80 FR 36258, June 24, 
2015) as paragraph (c)(1) and added new paragraph (c)(2) to this AD to 
state that installation of STC ST01219SE (http://rgl.faa.gov/
Regulatory_and_Guidance_Library/rgstc.nsf/0/
ebd1cec7b301293e86257cb30045557a/$FILE/ST01219SE.pdf) does not affect 
the ability to accomplish the actions required by this AD. Therefore, 
for airplanes on which STC ST01219SE is installed, a ``change in 
product'' alternative method of compliance (AMOC) approval request is 
not necessary to comply with the requirements of 14 CFR 39.17.

Request for Critical Design Configuration Control Limitation (CDCCL) 
Instructions

    SWA requested that we add instructions to paragraph (i) of the 
proposed AD (80 FR 36258, June 24, 2015) to specify that important 
CDCCL information must be observed during access and close-up while 
performing the actions specified in paragraph (i) of the proposed AD. 
SWA explained that Boeing Alert Service Bulletin 737-57A1323, dated 
December 5, 2014, does not contain any references to CDCCLs, despite 
the required access to the fuel tank, in order to perform either option 
1 or option 2 non-destructive test inspection requirements. SWA stated 
that the access and close-up steps indicate, as a reference, the 
maintenance planning document (section 4), which does not provide a 
clear path to the airplane maintenance manual section that addresses 
CDCCL requirements.
    We agree with the commenter's request. Boeing Alert Service 
Bulletin 737-57A1323, dated December 5, 2014, does not contain any 
references to CDCCLs that are part of the airworthiness limitations 
(AWLs). All applicable AWLs must still be observed while performing the 
actions mandated by this AD. We have revised paragraph (i) of this AD 
to state that while accomplishing the actions required by paragraph (i) 
of this AD, operators must ensure that all applicable CDCCLs are 
complied with.

Conclusion

    We reviewed the relevant data, considered the comments received, 
and determined that air safety and the public interest require adopting 
this AD with the changes described previously and minor editorial 
changes. We have determined that these minor changes:
     [Agr]re consistent with the intent that was proposed in 
the NPRM for correcting the unsafe condition; and
     Do not add any additional burden upon the public than was 
already proposed in the NPRM.
    We also determined that these changes will not increase the 
economic burden on any operator or increase the scope of this AD.

Related Service Information Under 1 CFR Part 51

    We reviewed Boeing Alert Service Bulletin 737-57A1323, dated 
December 5, 2014. The service information describes procedures for 
repetitive inspections for cracks on the left and right wing front spar 
lower chord, inspar skin, and wing skin, and corrective action. The 
service information is reasonably available because the interested 
parties have access to it through their normal course of business or by 
the means identified in the ADDRESSES section.

Costs of Compliance

    We estimate that this AD affects 331 airplanes of U.S. registry.
    We estimate the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                 Cost on U.S.
             Action                   Labor cost          Parts cost       Cost per product        operators
----------------------------------------------------------------------------------------------------------------
Inspection (28 Group 2            7 work[dash]hours   $0................  $595 per            $16,660 per
 airplanes).                       x $85 per hour =                        inspection cycle.   inspection cycle.
                                   $595 per
                                   inspection cycle.
Inspection and fastener           Up to 94            0.................  Up to $7,990 per    Up to $2,412,980
 installation (302 Group 3         work[dash]hours x                       inspection cycle.   per inspection
 airplanes).                       $85 per hour =                                              cycle.
                                   $7,990 per
                                   inspection cycle.
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[[Page 5895]]

    We have received no definitive data that will enable us to provide 
cost estimates for the actions specified for the Group 1 airplane in 
this AD.
    We also have received no definitive data that will enable us to 
provide cost estimates for the on-condition actions specified in this 
AD.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. Subtitle VII: Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701: ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    This AD will not have federalism implications under Executive Order 
13132. This AD will not have a substantial direct effect on the States, 
on the relationship between the national government and the States, or 
on the distribution of power and responsibilities among the various 
levels of government.
    For the reasons discussed above, I certify that this AD:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) Will not have a significant economic impact, positive or 
negative, on a substantial number of small entities under the criteria 
of the Regulatory Flexibility Act.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
1. The authority citation for part 39 continues to read as follows:

    Authority:  49 U.S.C. 106(g), 40113, 44701.

Sec.  39.13  [Amended]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive (AD):

2016-03-01 the Boeing Company: Amendment 39-18388; Docket No. FAA-
2015-1983; Directorate Identifier 2015-NM-020-AD.

(a) Effective Date

    This AD is effective March 10, 2016.

(b) Affected ADs

    None.

(c) Applicability

    (1) This AD applies to all The Boeing Company Model 737-100, -
200, -200C, -300, -400, and -500 series airplanes, certificated in 
any category.
    (2) Installation of Supplemental Type Certificate (STC) 
ST01219SE (http://rgl.faa.gov/Regulatory_and_Guidance_Library/
rgstc.nsf/0/ebd1cec7b301293e86257cb30045557a/$FILE/ST01219SE.pdf) 
does not affect the ability to accomplish the actions required by 
this AD. Therefore, for airplanes on which STC ST01219SE is 
installed, a ''change in product'' alternative method of compliance 
(AMOC) approval request is not necessary to comply with the 
requirements of 14 CFR 39.17.

(d) Subject

    Air Transport Association (ATA) of America Code 57, Wings.

(e) Unsafe Condition

    This AD was prompted by a report of a crack in the forward leg 
of the left front spar lower chord and cracks on the lower wing skin 
at three fastener holes common to the nacelle outboard side load 
fitting. We are issuing this AD to detect and correct fatigue 
cracking of the forward leg of the front spar lower chord, inspar 
skin, and wing skin common to the nacelle outboard side load 
fitting, which could adversely affect the structural integrity of 
the wing.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Inspections and Corrective Actions for Group 1 Airplanes

    For Group 1 airplanes identified in Boeing Alert Service 
Bulletin 737-57A1323, dated December 5, 2014: Within 120 days after 
the effective date of this AD, do inspections of the left and right 
wing front spar lower chord and inspar skin, and the left and right 
wing nacelle outboard side load fitting fastener holes common to the 
front spar lower chord and skin, and do all applicable corrective 
actions, using a method approved in accordance with the procedures 
specified in paragraph (k) of this AD.

(h) Repetitive Detailed Inspections and Corrective Actions

    For Group 2 and 3 airplanes identified in Boeing Alert Service 
Bulletin 737-57A1323, dated December 5, 2014: Except as provided by 
paragraph (j)(1) of this AD, at the applicable time specified in 
Table 1 of paragraph 1.E., ``Compliance,'' of Boeing Alert Service 
Bulletin 737-57A1323, dated December 5, 2014, do a detailed 
inspection for cracks on the left and right wing front spar lower 
chord and inspar skin, and do all applicable corrective actions, in 
accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin 737-57A1323, dated December 5, 2014, except as 
specified in paragraph (j)(2) of this AD. Do all applicable 
corrective actions before further flight. Repeat the inspection 
thereafter at the applicable interval specified in Table 1 of 
paragraph 1.E., ``Compliance,'' of Boeing Alert Service Bulletin 
737-57A1323, dated December 5, 2014, except in areas repaired in 
accordance with the procedures specified in paragraph (k) of this 
AD.

(i) Repetitive High Frequency Eddy Current (HFEC) Inspections and 
Corrective Actions

    For Group 3 airplanes identified in Boeing Alert Service 
Bulletin 737-57A1323, dated December 5, 2014: Except as provided by 
paragraph (j)(1) of this AD, at the applicable time specified in 
Table 2 or Table 3 of paragraph 1.E., ``Compliance,'' of Boeing 
Alert Service Bulletin 737-57A1323, dated December 5, 2014, do the 
actions specified in paragraphs (i)(1) or (i)(2) of this AD. Repeat 
the inspection specified in either paragraph (i)(1) or (i)(2) of 
this AD thereafter at the applicable interval specified in Table 2 
or Table 3 of paragraph 1.E., ``Compliance,'' of Boeing Alert 
Service Bulletin737-57A1323, dated December 5, 2014. While 
accomplishing the actions required by this paragraph, ensure that 
all applicable critical design configuration control limitations are 
complied with.
    (1) Do an HFEC open hole probe inspection for cracks of the left 
and right wing nacelle outboard side load fitting fastener holes 
common to the front spar lower chord and skin, and perform all 
applicable corrective actions, in accordance with Part 2, Option 1 
of the Accomplishment Instructions of Boeing Alert Service Bulletin 
737-57A1323, dated December 5, 2014, except as provided by paragraph 
(j)(2) of this AD. Do all applicable corrective actions before 
further flight.
    (2) Do an HFEC surface probe inspection for cracks in the wing 
inspar skin, and perform all applicable corrective actions, in 
accordance with Part 2, Option 2 of the Accomplishment Instructions 
of Boeing Alert Service Bulletin 737-57A1323, dated December 5, 
2014, except as provided by paragraph (j)(2) of this AD. Do all 
applicable corrective actions before further flight.

(j) Exceptions to Service Information Specifications

    (1) Where paragraph 1.E., ``Compliance,'' of Boeing Alert 
Service Bulletin 737-57A1323, dated December 5, 2014, specifies a 
compliance time ``after the original issue date of this service 
bulletin,'' this AD requires

[[Page 5896]]

compliance within the specified compliance time ``after the 
effective date of this AD.''
    (2) Although Boeing Alert Service Bulletin 737-57A1323, dated 
December 5, 2014, specifies to contact Boeing for repair 
instructions, and specifies that action as ``RC'' (Required for 
Compliance), this AD requires repair before further flight using a 
method approved in accordance with the procedures specified in 
paragraph (k) of this AD.

(k) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Los Angeles Aircraft Certification Office 
(ACO), FAA, has the authority to approve AMOCs for this AD, if 
requested using the procedures found in 14 CFR 39.19. In accordance 
with 14 CFR 39.19, send your request to your principal inspector or 
local Flight Standards District Office, as appropriate. If sending 
information directly to the manager of the ACO, send it to the 
attention of the person identified in paragraph (l) of this AD. 
Information may be emailed to: 9-ANM-LAACO-AMOC-Requests@faa.gov.
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair, modification, or alteration required by this AD 
if it is approved by the Boeing Commercial Airplanes Organization 
Designation Authorization (ODA) that has been authorized by the 
Manager, Los Angeles ACO, to make those findings. To be approved, 
the repair method, modification deviation, or alteration deviation 
must meet the certification basis of the airplane, and the approval 
must specifically refer to this AD.
    (4) Except as required by paragraph (j)(2) of this AD: For 
service information that contains steps that are labeled as Required 
for Compliance (RC), the provisions of paragraphs (k)(4)(i) and 
(k)(4)(ii) apply.
    (i) The steps labeled as RC, including substeps under an RC step 
and any figures identified in an RC step, must be done to comply 
with the AD. An AMOC is required for any deviations to RC steps, 
including substeps and identified figures.
    (ii) Steps not labeled as RC may be deviated from using accepted 
methods in accordance with the operator's maintenance or inspection 
program without obtaining approval of an AMOC, provided the RC 
steps, including substeps and identified figures, can still be done 
as specified, and the airplane can be put back in an airworthy 
condition.

(l) Related Information

    For more information about this AD, contact Jennifer 
Tsakoumakis, Aerospace Engineer, Airframe Branch, ANM-120L, FAA, Los 
Angeles ACO, 3960 Paramount Boulevard, Lakewood, CA 90712-4137; 
phone: 562-627-5264; fax: 562-627-5210; email: 
jennifer.tsakoumakis@faa.gov.

(m) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the service information listed 
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) Boeing Alert Service Bulletin 737-57A1323, dated December 5, 
2014.
    (ii) Reserved.
    (3) For Boeing service information identified in this AD, 
contact Boeing Commercial Airplanes, Attention: Data & Services 
Management, P.O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; 
telephone 206-544-5000, extension 1; fax 206-766-5680; Internet 
https://www.myboeingfleet.com.
    (4) You may view this service information at the FAA, Transport 
Airplane Directorate, 1601 Lind Avenue SW., Renton, WA. For 
information on the availability of this material at the FAA, call 
425-227-1221.
    (5) You may view this service information that is incorporated 
by reference at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued in Renton, Washington, on January 25, 2016.
Michael Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2016-01827 Filed 2-3-16; 8:45 am]
BILLING CODE 4910-13-P
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